Fiche publication
Date publication
novembre 2014
Journal
Journal of virology
Auteurs
Membres identifiés du Cancéropôle Est :
Pr BAUMERT Thomas
Tous les auteurs :
Bankwitz D, Vieyres G, Hueging K, Bitzegeio J, Doepke M, Chhatwal P, Haid S, Catanese MT, Zeisel MB, Nicosia A, Baumert TF, Kaderali L, Pietschmann T
Lien Pubmed
Résumé
Hepatitis C virus (HCV) particles associate with lipoproteins and infect cells by using at least four cell entry factors. These factors include scavenger receptor class B type I (SR-BI), CD81, claudin 1 (CLDN1), and occludin (OCLN). Little is known about specific functions of individual host factors during HCV cell entry and viral domains that mediate interactions with these factors. Hypervariable region 1 (HVR1) within viral envelope protein 2 (E2) is involved in the usage of SR-BI and conceals the viral CD81 binding site. Moreover, deletion of this domain alters the density of virions. We compared lipoprotein interaction, surface attachment, receptor usage, and cell entry between wild-type HCV and a viral mutant lacking this domain. Deletion of HVR1 did not affect CD81, CLDN1, and OCLN usage. However, unlike wild-type HCV, HVR1-deleted viruses were not neutralized by antibodies and small molecules targeting SR-BI. Nevertheless, modulation of SR-BI cell surface expression altered the infection efficiencies of both viruses to similar levels. Analysis of affinity-purified virions revealed comparable levels of apolipoprotein E (ApoE) incorporation into viruses with or without HVR1. However, ApoE incorporated into these viruses was differentially recognized by ApoE-specific antibodies. Thus, SR-BI has at least two functions during cell entry. One of them can be neutralized by SR-BI-targeting molecules, and it is critical only for wild-type HCV. The other one is important for both viruses but apparently is not inactivated by the SR-BI binding antibodies and small molecules evaluated here. In addition, HVR1 modulates the conformation and/or epitope exposure of virus particle-associated ApoE.
Mots clés
Cell Line, Claudin-1, metabolism, Gene Deletion, Hepacivirus, physiology, Hepatocytes, virology, Host-Pathogen Interactions, Humans, Lipoproteins, metabolism, Occludin, metabolism, Protein Binding, Protein Interaction Mapping, Scavenger Receptors, Class B, metabolism, Tetraspanin 28, metabolism, Viral Proteins, genetics, Virus Internalization
Référence
J. Virol.. 2014 Nov;88(21):12644-55
